"Islamic State of Iraq and the Levant" (ISIL) fighters were shaving their beards and changing hideouts in Mosul, residents said, as Iraqi forces moved ever closer to the city Wednesday (October 26th) and civilians fled in growing numbers.

Several residents told AFP the militants seemed to be preparing for an assault after recent advances on the eastern front brought elite Iraqi forces to within five kilometres of city limits.

"I saw some ISIL members and they looked completely different from the last time I saw them," said a resident of eastern Mosul who gave his name as Abu Saif.

"They had trimmed their beards and changed their clothes," the former businessman said. "They must be scared... they are also probably preparing to escape the city."

Residents and military officials said many ISIL fighters had relocated from eastern Mosul to their traditional bastions on the western bank of the Tigris river, closer to escape routes to Syria.

The sounds of fighting on the northern and eastern fronts of the Mosul offensive could now be heard inside the city, residents said, and international coalition aircraft were flying lower over the city than usual.

On Wednesday, the 10th day of the operation, Iraqi forces liberated six new villages and destroyed several car bombs and weapons caches, Ninawa operations commander Nejim Edin Karim al-Jubury told Diyaruna.

"Iraqi forces are operating with a high level of co-ordination," he said.

"God willing, we shall declare victory soon. We ask the people of Mosul, whether Muslims, Christians, Shabak or Yazidis, to pray for this day," he added.

Meanwhile, the Ministry of Defence announced the liberation of the Tel Keppe gas plant, north-east of Mosul, from ISIL.

Units of the Iraqi army’s 16th Division liberated the Tel Keppe gas plant and inflicted heavy losses on ISIL "in a battle that lasted for several hours", the ministry said in a statement.

'Wave of displaced'

Some 3,000 to 5,000 ISIL fighters are believed to be inside Mosul, Iraq's second city, alongside more than a million trapped civilians.

Aid workers have warned of a major potential humanitarian crisis once fighting begins inside the city itself.

An Iraqi minister said Wednesday that more than 3,300 civilians fleeing the fighting had sought help from the government the day before, the most for a single day so far.

There was "a big wave of displaced people that is considered the greatest number since the start of the military operation to liberate Ninawa province," Displacement and Migration Minister Jassem Mohammed al-Jaf said in a statement.

Numbers of displaced residents were growing but stood at a relatively low 8,940 on Wednesday, according to a UN tally, because most of the fighting so far has taken place in sparsely populated areas.

Civilians in villages on the eastern outskirts of Mosul were being bused to a camp near Khazir, AFP reported.

"We used to live in terror night and day, the shelling was coming closer. ISIL controlled our lives, so we decided to flee," said Essam Saadou, a 22-year-old student.

Hesham al-Hamdani, 59, described his safe exit from al-Hamdaniya, east of Mosul, as "a new chapter for me and my family".

"Iraqi forces received us well and we were taken to a tent. We hope that we will not stay here for long. We are counting on our heroic forces to clear our area of terrorists so we can return quickly," he told Diyaruna.

Sights set on al-Raqa

As the noose tightened on Mosul, 13 defence chiefs from the 60-nation coalition meeting in Paris set their sights on Syria's al-Raqa, which would be the last major city under ISIL control if it loses Mosul.

"We have already begun laying the groundwork for our partners to commence the isolation of al-Raqa," US Defence Secretary Ashton Carter said after the talks.

The coalition has provided support in the form of thousands of airstrikes, and training for Iraqi forces and advisers on the ground.

British Defence Minister Michael Fallon said Wednesday he hoped operations will begin shortly against ISIL in al-Raqa.

"We hope a similar operation will begin towards al-Raqa in the next few weeks," Fallon said as he arrived for a two-day NATO defence ministers meeting in Brussels.

Meanwhile, France said it had extended the mission of its aircraft carrier, the Charles de Gaulle, in the eastern Mediterranean until at least mid-December to help the offensive on Mosul.